Somatic symptoms and internalizing problems in urban youth: a cross-cultural comparison of Czech and Russian adolescents

Somatic symptoms and internalizing problems in urban youth: a cross-cultural comparison of Czech... Abstract Background Although the association between somatic complaints and internalizing problems (anxiety, somatic anxiety and depression) is well established, it remains unclear whether the pattern of this relationship differs by gender and in different cultures. The aim of this study was to examine cross-cultural and gender-specific differences in the association between somatic complaints and internalizing problems in youth from the Czech Republic and Russia. Methods The Social and Health Assessment, a self-report survey, was completed by representative community samples of adolescents, age 12–17 years, from the Czech Republic (N = 4770) and Russia (N = 2728). Results A strong association was observed between somatic complaints and internalizing psychopathology. Although the levels of internalizing problems differed by country and gender, they increased together with and largely in a similar way to somatic complaints for boys and girls in both countries. Conclusion The association between somatic symptoms and internalizing problems seems to be similar for boys and girls across cultures. Introduction Population-based studies suggest that somatic complaints are common among youth with nearly one-half of all children and adolescents reporting at least one symptom during the last 2 weeks.1,2 Types of somatic complaint vary with age,3 initially being monosymptomatic, they appear to become polysymptomatic over time.4 Somatic complaints often lack a medical explanation but indicate a higher risk of problems in several areas. They are also associated with an overuse of the health care system1,3 and increase the risk of unnecessary medical examinations and treatments.5 In general, somatic complaints have a negative impact on the quality of life, not only for the children themselves but also for their families,6 and may precede the development of somatic symptom disorders in adulthood.4 Somatic complaints are also associated with poor academic performance7 and school absence, which can lead to greater social isolation.8 There is also a strong association between somatic complaints and psychiatric problems, especially anxiety and depression.3,8 In depressed adolescents multiple somatic symptoms reflect a higher severity of depression9 and even in adolescents without a previous history of depression, somatic symptoms predict depression.10 Some studies have suggested that the association between somatic complaints and anxiety is stronger than the association between somatic complaints and depression,11 while others have indicated that the frequency of somatic complaints increases with the severity of depression, regardless of anxiety levels12 or that the association of somatic complaints with anxiety and depression may be of equal strength.13 In addition, the somatic component of anxiety (i.e. bodily symptoms of increased physiological arousal, such as an increase in heart rate and muscle tension)14 may have an independent role in the development of somatic complaints, even after controlling for internalizing problems.15 Girls typically report more somatic symptoms than boys.3,16 This gender difference seems to increase in puberty with adolescent girls reporting somatic symptoms at an increasing rate, while reporting levels in boys fall.17 It has been suggested that somatic symptoms in girls have a stronger association with anxiety and depression, while among boys they are more likely to be associated with disruptive behaviour.18 Some studies have suggested that the higher prevalence of anxiety and depression among females can fully account for gender differences in the reporting of somatic complaints,19 while others have shown that although gender differences decrease when adjusting for internalizing symptoms, they remain significant.20 There is some evidence that socio-cultural factors can influence the prevalence and nature of symptoms exhibited in somatization disorders.21 Some authors suggest that symptoms can be selectively expressed in ways accepted in a given culture22,23 and that the presentation of symptoms can depend on cultural attitudes that further determine how an illness is perceived and identified. For example, an earlier study showed that Asian patients were more likely to report somatic rather than emotional symptoms, although they did acknowledge having emotional symptoms when questioned further.24 Furthermore, explanatory models vary across cultures, with symptoms being attributed to medical illness, family, work, environmental stress or culture-specific phenomena.25 At the same time, a large cross-cultural study of somatization conducted by the World Health Organization (WHO)26 has indicated that the types of somatic complaint are fairly uniform throughout the world and are highly co-morbid with anxiety, depression and other psychiatric problems, and that there is an association between somatization disorder and significant functional impairment.26 Another study focusing on adolescents demonstrated that although many kinds of psychopathology were cross-culturally different, the level of somatic complaints was quite similar.27 Some studies have even suggested that the patterns of comorbidity, impairment, risk-factors and treatment seeking are cross-culturally similar, even though they may vary in magnitude or intensity.28 Although the association between somatic complaints, anxiety and depression is established, further research is needed to determine whether internalizing problems influence somatic complaints in different cultures in a similar fashion. This study aimed to investigate cross-cultural similarities (here represented by Russia and the Czech Republic) in the relation between somatic complaints and internalizing problems. The study hypothesized that an increased severity of somatic complaints relates to increasing levels of internalizing problems in both cultures in a similar way. We further hypothesized that these relationships are likely to be gender-specific, with higher levels of internalizing problems in relation to somatic complaints among girls. Methods Participants Data in this study come from the Social and Health Assessment (SAHA) conducted in the Czech Republic and Russia. The primary aim of this study was to determine the factors associated with adolescent health and well-being. The study sites were the following: Russia [the city of Arkhangelsk (population 356 000)] and the Czech Republic [the capital Prague (population 1.2 million) and all 12 regional capitals (population 50 000–400 000)]. The survey methodology has been previously described elsewhere.29 In brief, in Arkhangelsk and the Czech study locations, data were collected from representative samples of students aged 12–17 and 12–18, respectively. Only general public schools were included in the study (i.e. schools with special education programmes were excluded). Permission to conduct the study in selected schools was obtained from the respective city administrations. With regard to the Russian sample, ∼30 000 youth are in the 12- to 17-year-old age range in the city of Arkhangelsk. To obtain a representative sample, 14 schools were randomly selected from 71 eligible schools, yielding 210 classes in grades 6–11. For the Czech sample, stratified probability sampling of schools, according to location and school type, was conducted to identify a national probability sample of youth aged 12–18 years. The students that participated belonged to classes that had been randomly selected within randomly selected schools (N = 150 schools). For comparability, this study was limited to those adolescents who were aged 12–17 years old [M (SD) = 14.76 (1.55)] with the analytical sample thus comprising 2728 adolescents (1121 boys) from Russia and 4770 adolescents (2080 boys) from the Czech Republic. Response rates for these surveys were high, with only 3.6% of children refusing to participate in Russia and 1.4% in the Czech Republic (N = 98 and 67, respectively). Procedure In both countries, students completed the survey in their classrooms during a normal school day. Written informed consent was obtained from all participants prior to the survey administration, and both parents (for their children) and children had the right to refuse to participate. Ethical approval for the study was obtained from the Northern State Medical University in Arkhangelsk, Russia and the Institute of Psychology, Academy of Sciences of the Czech Republic, v.v.i. Measures The SAHA, a self-report questionnaire developed by Weissberg et al.30 and adapted by Schwab-Stone et al.31 served as the basis for this study. The instrument was originally developed in the USA in collaboration with the school system, to monitor the emotional and behavioural well-being of middle and high school students and to develop curricula to more adequately meet the needs of the students. All the measures, described below, were used in the SAHA survey and included both new scales that were specifically developed for the survey and pre-exisiting scales that had been used previously with similar populations. Somatic complaints were measured with a scale that consisted of nine items representing somatic symptoms commonly reported by children and adolescents. Only symptoms that had a prevalence rate above 5% (as suggested by Taylor et al.32 were used in this study). The scale items included felt my health should be better, had headaches, worried a lot about health, had stomach aches, had aches or pains, had nausea, had rashes or other skin problems, didn’t feel well and vomited. The ‘function loss’ symptoms were not included, as they tend to be uncommon (6–20 times less frequent than other somatic complaints29 and usually represent either a true loss of function or dissociative symptomatology). Students reported on somatic symptoms during the past month on a three-point scale [Not True (0), Somewhat True (1) and Certainly True (2)]. Cronbach’s α for this scale was 0.83. Three groups were formed according to the reported level of somatic complaints, namely those that reported relatively low levels of somatic complaints (the lower 75% of participants), those that reported a prevalence that fell between the 75th and 95th percentile, and finally those that reported the highest levels of somatic complaints, constituting the top 5%. These groups were subsequently categorized as ‘low’, ‘middle’ and ‘high’, respectively, in terms of the level of their somatic complaints. Somatic anxiety was assessed by a scale that consisted of seven items describing somatic experiences (bodily or physiological processes or sensations) frequently associated with anxiety in children and adolescents and commonly used in anxiety scales.33–35 Items in the present scale were compiled by the authors from existing scales and further modified and expanded after a series of discussions with a group of paediatricians, child psychiatrists and psychologists about the typical somatic symptoms experienced by children in relation to anxiety. Symptoms were listed after an introductory phrase (‘Often when I worry…’) with response options of ‘Not True (0), Somewhat True (1) or Certainly True (2) for you’. The scale items included I have trouble catching my breath; my heart beats fast; my hands feel sweaty; I feel shaky; I feel tense or uptight; my hands feel cold and I feel butterflies in my stomach. The scale does not overlap with the somatic complaints scale, as demonstrated previously by a joint factor analysis of the somatic anxiety and somatic complaints scales.15 The Cronbach α for the somatic anxiety scale was 0.78. Depressive symptoms were assessed using an adaptation of the Centre for Epidemiologic Studies-Depression Scale (CES-D).36 Both the CES-D37 and its modified/shortened versions38 have demonstrated excellent psychometric properties with adolescents. In this study, the questionnaire consisted of 10 items (i.e. I did not feel like eating, my appetite was poor; I felt that I could not shake off my sad feelings even with help from my family or friends; I felt lonely; I felt like crying; I felt really down; I felt that many bad things were my fault; I was tired; I have lost my interest in other people or things; I didn’t like myself and I felt bothered by people and things). Students reported on the presence of symptoms in the past month using a three-point scale [Not True (0), Somewhat True (1) and Certainly True (2)]. Scores were summed to create a total score that ranged from 0 to 20 with higher scores indicating increased depressive symptoms. The scale had good internal consistency (α 0.80). Anxiety was assessed by a 12-item scale,15 reflecting on cognitive–affective and behavioural modes of anxiety, including worrisome, preoccupying thoughts or unpleasant feelings about oneself or external stimuli (e.g. worrying about being liked; feeling nervous when called on in class and worrying about the future). Students reported on the presence of anxiety symptoms on a three-point scale [Not True (0), Somewhat True (1) and Certainly True (2)]. The scale had good internal consistency (α 0.86). Statistical analyses Data were analyzed using the Statistical Package for the Social Sciences (SPSS-22.0). Univariate analyses of covariance (Uni-ANCOVA) were conducted to assess differences in the levels of somatic symptoms between girls and boys in the two countries (with age used as a covariate). Multivariate analyses of covariance (MANCOVA) were performed to assess differences in the levels of internalizing problems (as assessed by depressive, anxiety and somatic anxiety symptoms) in boys and girls, who were divided into three groups in relation to the reported levels of somatic complaints (‘low’, ‘middle’ and ‘high’). Hence, we used a 3 (level of somatic complaints) × 2 (country) × 2 (gender) design for the internalizing problems, while controlling for age as a covariate. Results Table 1 presents the descriptive statistics [M (SD)] for the MANCOVA regarding differences in internalizing problems according to the level of somatic complaints for boys and girls in both countries. The Univariate Analysis of Variance revealed significantly higher levels of somatic complaints in girls in both countries: [M (SD) = 4.99(3.67) in girls vs. 3.61(3.06) in boys in the Czech Republic and M (SD) = 5.53(3.64) in girls vs. 4.59(3.64) in boys in Russia]. The between-subject effects (with age used as a covariate) were significant for country F(1, 7607) = 930.04, η2 = 0.011, P < 0.001; for gender F(1, 7607) = 2271.90, η2 = 0.025, P < 0.001 and for the interaction effect of country by gender F(1, 7607) = 87.59, η2 = 0.001, P < 0.01. The effect of age was also significant [F(1, 7607) = 201.02, η2 = 0.002, P < 0.001], suggesting higher levels of somatic complaints in older youth. Table 1 Internalizing scores [M (SD)] in the Czech Republic and Russia by the level of somatic complaints in boys (B) and girls (G) Level of somatic complaints Low Middle High Depressive symptoms Czech B 2.71 (2.70) 5.59 (3.78) 8.29 (4.70) G 3.81 (3.39) 6.82 (4.13) 10.22 (4.63) Russia B 3.94 (3.42) 6.71 (4.13) 8.72 (4.44) G 5.19 (3.82) 7.79 (3.85) 10.12 (4.13) Anxiety Czech B 8.06 (4.50) 10.90 (4.59) 11.37 (5.83) G 9.67 (4.41) 12.01 (4.51) 14.17 (4.77) Russia B 11.52 (5.80) 13.27 (5.52) 14.75 (5.17) G 12.75 (5.46) 15.21 (5.17) 16.64 (4.92) Somatic anxiety Czech B 2.70 (2.30) 4.25 (2.80) 5.74 (3.61) G 4.10 (2.59) 5.87 (2.75) 7.31 (3.10) Russia B 2.94 (2.55) 4.33 (2.93) 6.06 (4.00) G 4.22 (2.69) 5.45 (2.92) 6.94 (3.14) Level of somatic complaints Low Middle High Depressive symptoms Czech B 2.71 (2.70) 5.59 (3.78) 8.29 (4.70) G 3.81 (3.39) 6.82 (4.13) 10.22 (4.63) Russia B 3.94 (3.42) 6.71 (4.13) 8.72 (4.44) G 5.19 (3.82) 7.79 (3.85) 10.12 (4.13) Anxiety Czech B 8.06 (4.50) 10.90 (4.59) 11.37 (5.83) G 9.67 (4.41) 12.01 (4.51) 14.17 (4.77) Russia B 11.52 (5.80) 13.27 (5.52) 14.75 (5.17) G 12.75 (5.46) 15.21 (5.17) 16.64 (4.92) Somatic anxiety Czech B 2.70 (2.30) 4.25 (2.80) 5.74 (3.61) G 4.10 (2.59) 5.87 (2.75) 7.31 (3.10) Russia B 2.94 (2.55) 4.33 (2.93) 6.06 (4.00) G 4.22 (2.69) 5.45 (2.92) 6.94 (3.14) Table 1 Internalizing scores [M (SD)] in the Czech Republic and Russia by the level of somatic complaints in boys (B) and girls (G) Level of somatic complaints Low Middle High Depressive symptoms Czech B 2.71 (2.70) 5.59 (3.78) 8.29 (4.70) G 3.81 (3.39) 6.82 (4.13) 10.22 (4.63) Russia B 3.94 (3.42) 6.71 (4.13) 8.72 (4.44) G 5.19 (3.82) 7.79 (3.85) 10.12 (4.13) Anxiety Czech B 8.06 (4.50) 10.90 (4.59) 11.37 (5.83) G 9.67 (4.41) 12.01 (4.51) 14.17 (4.77) Russia B 11.52 (5.80) 13.27 (5.52) 14.75 (5.17) G 12.75 (5.46) 15.21 (5.17) 16.64 (4.92) Somatic anxiety Czech B 2.70 (2.30) 4.25 (2.80) 5.74 (3.61) G 4.10 (2.59) 5.87 (2.75) 7.31 (3.10) Russia B 2.94 (2.55) 4.33 (2.93) 6.06 (4.00) G 4.22 (2.69) 5.45 (2.92) 6.94 (3.14) Level of somatic complaints Low Middle High Depressive symptoms Czech B 2.71 (2.70) 5.59 (3.78) 8.29 (4.70) G 3.81 (3.39) 6.82 (4.13) 10.22 (4.63) Russia B 3.94 (3.42) 6.71 (4.13) 8.72 (4.44) G 5.19 (3.82) 7.79 (3.85) 10.12 (4.13) Anxiety Czech B 8.06 (4.50) 10.90 (4.59) 11.37 (5.83) G 9.67 (4.41) 12.01 (4.51) 14.17 (4.77) Russia B 11.52 (5.80) 13.27 (5.52) 14.75 (5.17) G 12.75 (5.46) 15.21 (5.17) 16.64 (4.92) Somatic anxiety Czech B 2.70 (2.30) 4.25 (2.80) 5.74 (3.61) G 4.10 (2.59) 5.87 (2.75) 7.31 (3.10) Russia B 2.94 (2.55) 4.33 (2.93) 6.06 (4.00) G 4.22 (2.69) 5.45 (2.92) 6.94 (3.14) The main effect for the level of somatic complaints for the total group was significant [Wilks’ lambda = 0.810; F(6, 14 966) = 276.53, P < 0.000, η2 = 0.010], with increasing internalizing problems associated with an increasing level of somatic complaints. The main effect for gender was significant [Wilks’ lambda = 0.972; F(3, 7483) = 72.73, P < 0.000, η2 = 0.028], demonstrating a difference between the variables of interest for boys and girls. The main effect for country was significant [Wilks’ lambda = 0.958; F(3, 7483) = 108.73, P < 0.000, η2 = 0.042], suggesting differences in the baseline levels of internalizing problems between youth in the Czech Republic and in Russia (higher in Russia). The main effect for age was also significant [Wilks’ lambda = 0.984; F(3, 7483) = 39.93, P < 0.000, η2 = 0.016], demonstrating a difference between the variables of interest by age. Pearson’s correlational analyses showed a clear increase in symptoms with increasing age (data not shown). In regard to the interaction effects, the interaction effect for somatic complaints × country was weakly significant [Wilks’ lambda = 0.998; F(6, 14 966) = 2.71, P < 0.05, η2 = 0.001], suggesting that the increase in internalizing problems that occurs along with an increase in somatic complaints follows a slightly different pattern in these two cultures. However, the interaction effect for somatic complaints × gender was not significant [Wilks’ lambda = 0.999; F(6, 14 966) = 1.06, n.s., η2 = 0.000], which indicates that patterns of internalizing problems in relation to somatic complaints were not gender-specific. The interaction effect for country × gender was not significant [Wilks’ lambda = 0.999; F(3, 7483) = 1.73, n.s., η2 = 0.001], suggesting that the relation between internalizing problems and somatic complaints in boys and girls was similar in both countries. Finally, the interaction effect for somatic complaints × country × gender was also not significant [Wilks’ lambda = 0.998; F(6, 14 966) = 2.15, n.s., η2 = 0.001]. This suggests that despite substantial differences in the levels of internalizing problems by country, by gender and by the different levels of somatic complaints, that internalizing problems and somatic complaints increase together in a similar way among boys and girls in both countries. Table 2 presents effect sizes for each dependent variable (depressive, anxiety and somatic anxiety symptoms), as well as the summary statistics. In both samples, all three types of internalizing problem increased along with the level of somatic complaints and the age of the participants. The results suggest that the interaction effect of somatic complaints × country on internalizing problems was predominantly related to differences in co-morbid depressive symptoms. Table 2 Effect sizes for each dependent variable and summary statistics (η2, P) Depressive symptoms Anxiety symptoms Somatic anxiety Age 0.009, <0.001 0.001, <0.05 0.005, <0.001 Somatic complaints 0.161, <0.001 0.057, <0.001 0.092, <0.001 Country 0.004, <0.001 0.035, <0.001 0.000, ns Gender 0.012, <0.001 0.012, <0.001 0.022, <0.001 Somatic complaints by country 0.001, <0.05 0.000, ns 0.001, ns Country by gender 0.000, ns 0.000, ns 0.001, <0.05 Somatic complaints by gender 0.000, ns 0.000, ns 0.000, ns Somatic complaints by country by gender 0.000, ns 0.001, ns 0.000, ns Depressive symptoms Anxiety symptoms Somatic anxiety Age 0.009, <0.001 0.001, <0.05 0.005, <0.001 Somatic complaints 0.161, <0.001 0.057, <0.001 0.092, <0.001 Country 0.004, <0.001 0.035, <0.001 0.000, ns Gender 0.012, <0.001 0.012, <0.001 0.022, <0.001 Somatic complaints by country 0.001, <0.05 0.000, ns 0.001, ns Country by gender 0.000, ns 0.000, ns 0.001, <0.05 Somatic complaints by gender 0.000, ns 0.000, ns 0.000, ns Somatic complaints by country by gender 0.000, ns 0.001, ns 0.000, ns Table 2 Effect sizes for each dependent variable and summary statistics (η2, P) Depressive symptoms Anxiety symptoms Somatic anxiety Age 0.009, <0.001 0.001, <0.05 0.005, <0.001 Somatic complaints 0.161, <0.001 0.057, <0.001 0.092, <0.001 Country 0.004, <0.001 0.035, <0.001 0.000, ns Gender 0.012, <0.001 0.012, <0.001 0.022, <0.001 Somatic complaints by country 0.001, <0.05 0.000, ns 0.001, ns Country by gender 0.000, ns 0.000, ns 0.001, <0.05 Somatic complaints by gender 0.000, ns 0.000, ns 0.000, ns Somatic complaints by country by gender 0.000, ns 0.001, ns 0.000, ns Depressive symptoms Anxiety symptoms Somatic anxiety Age 0.009, <0.001 0.001, <0.05 0.005, <0.001 Somatic complaints 0.161, <0.001 0.057, <0.001 0.092, <0.001 Country 0.004, <0.001 0.035, <0.001 0.000, ns Gender 0.012, <0.001 0.012, <0.001 0.022, <0.001 Somatic complaints by country 0.001, <0.05 0.000, ns 0.001, ns Country by gender 0.000, ns 0.000, ns 0.001, <0.05 Somatic complaints by gender 0.000, ns 0.000, ns 0.000, ns Somatic complaints by country by gender 0.000, ns 0.001, ns 0.000, ns As the differences by outcome, country and gender might have been masked by use of the MANCOVA analysis (i.e. by simultaneously assessing all three outcomes in one model), we also attempted to examine each outcome separately to determine whether the patterns that are reported from the MANCOVA were the same for each outcome individually. This produced very similar results. Discussion In this study, we sought to investigate the relationship between somatic complaints and internalizing problems in a cross-cultural context, and to examine whether the association is country and gender specific. The hypothesis that the relation between somatic complaints and internalizing problems is the same across cultures was not confirmed, with the relation between depressive symptoms and somatic complaints seeming to underlie the slightly different patterns observed in the two countries. We further hypothesized that the relationship between somatic complaints and internalizing problems is different among boys and girls but this hypothesis was refuted, as the results suggest that internalizing problems and somatic complaints increase in a similar, non–gender-specific way in both countries. In general, our results provide strong support for the earlier established association between somatic symptoms, on the one hand, and anxiety and depression, on the other hand, where an increase in the number of somatic complaints was accompanied by an increase in the level of internalizing problems. Effect sizes for the association were moderate, which is in line with the results from some previous studies39 and points to the fact that somatic symptoms may occur without concurrent anxiety or depression and hence, are not solely bodily expressions of internalizing problems. In addition, our study confirmed the previously suggested association between somatic anxiety and somatic complaints,15 further supporting the finding that somatic anxiety is associated with somatic complaints independently of anxiety and depression. This finding may have implications for clinical practice especially when selecting an intervention as it suggests that somatic anxiety may be one reason for children to have a focus on their bodily feelings that further leads to somatization. Cognitive–behavioural interventions commonly have a primary focus on treating either physical symptoms (e.g. pain) or anxiety, although they do demonstrate some efficacy for reducing somatic symptoms.40 However, using such cognitive–behavioural interventions may be more beneficial if they also consider the interaction of physical complaints and anxiety. As to our first hypothesis, Russian youths generally reported higher levels of internalizing problems than those in the Czech Republic, although it is uncertain whether the results from this representative sample from the north of Russia can be generalized to the general adolescent population in the whole of Russia. Interestingly, the relation between internalizing and somatic symptoms was slightly different in the Czech Republic and Russia, which was related to the differential influence of depressive symptoms. The question about the specific nature of such cultural influences needs to be approached with other research designs. So far, there have been surprisingly few studies on mental health problems in adolescents from Eastern Europe in general, or in Russian or Czech youth, in particular. A study comparing Russian and British children found that the patterns of internalizing and externalizing problems were similar between the two groups, even though Russian children had a somewhat higher level of symptoms.41 Somatization has previously been thought to be particularly common in non-Western cultures but conclusions are complicated by the lack of comparable standardized methodologies, as diagnostic criteria derived from one culture may not necessarily be applicable to another. A large cross-cultural study of somatization conducted by the WHO found that although the rates of somatization varied markedly across cultures, no clear cultural, economic or geographic factors could be identified to account for the variation.26 Another study demonstrated that although many kinds of psychopathology in adolescents were cross-culturally different, the levels of somatic complaints were quite similar.27 Contrary to our second hypothesis, the patterns of increase in internalizing problems in relation to the increase in somatic complaints were not gender-specific. This suggests that gender-specific differences in the prevalence of anxiety and depression may not fully account for differences in somatic symptoms. Similar findings have been reported by Haug et al.13 who also found that the association between somatic complaints and internalizing problems was equally strong in men and women13 but differ from those by Beck8 and Perquin et al.42 who reported gender-specific patterns in the association, with girls tending to report not only more anxiety and depression but also more somatic symptoms than do boys. This study has a number of limitations. First, as this study used adolescent self-reports, the possibility of recall bias and false reporting cannot be excluded.43 Second, we also lacked any relevant medical information (doctor’s reports etc.,) which means that we cannot rule out the possibility that the reported symptoms might have been explained by a medical condition. Third, the somatic complaints scale that was used in this study was limited to nine items and did not take into consideration the potential presence of culture-specific symptoms. Fourth, selection bias can often be an issue in population-based studies, although we would argue that it was unlikely to have been a problem in this study considering the thorough randomization procedure and low refusal rate. Finally, the cross-sectional nature of the study does not allow conclusions to be drawn about causality or the direction of the relationship between somatic complaints and internalizing problems. The study’s strengths are a large sample size, high response rates and a focus on less common study groups: geographically representative samples from the Czech Republic and Russia. The scales we used allowed us to control for the possible overlap between depression, anxiety, somatic anxiety and somatic symptoms, thus making it possible to assess the contribution of these conditions separately. Future research should consider validating somatic symptoms by medical examination, complementing self-reports by obtaining additional information from sources like parents or medical records, as well as include more items on somatic symptoms and their consequences. Even if somatic symptoms are influenced by culture in their presentation, the presence of an association with psychopathology seems to be independent of culture in boys and girls, supporting the notion that similar treatment methods may be used in different countries.28 Studying the association between somatic and psychological symptoms may be a promising method to discover cultural differences concerning symptom development that can be used as a complement to only comparing symptom frequencies per se. Future research should address how such differences could be interpreted, as well as assess the extent to which somatic complaints impact on the daily life of youths, lead to functional impairment and/or health care seeking behaviour from a cross-cultural perspective. Funding This work was supported by Czech Republic for long-term strategic development of research organization (grant number RVO: 68081740). Conflicts of interest: None declared. Key points Results strongly support the earlier established association between somatic symptoms and anxiety and depression. Evidence indicates that the level of internalizing problems increases along with the level of somatic complaints. The patterns of association between somatic complaints and internalizing problems are similar for boys and girls in different cultures. 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Google Scholar CrossRef Search ADS PubMed 18 Egger HL , Costello EJ , Erkanli A , Angold A . Somatic complaints and psychopathology in children and adolescents: stomach aches, musculoskeletal pains, and headaches . J Am Acad Child Adolesc Psychiatry 1999 ; 38 : 852 – 86 . Google Scholar CrossRef Search ADS PubMed 19 Piccinelli M , Simon G . Gender and cross-cultural differences in somatic symptoms associated with emotional distress. An international study in primary care . Psychol Med 1997 ; 27 : 433 – 44 . Google Scholar CrossRef Search ADS PubMed 20 Kroenke K , Spitzer RL . Gender differences in the reporting of physical and somatoform symptoms . Psychosom Med 1998 ; 60 : 150 – 5 . Google Scholar CrossRef Search ADS PubMed 21 Davey GC . Psychopathology: Research, Assessment and Treatment in Clinical Psychology . Malden, MA : Blackwell Publishing , 2008 . 22 Kleinman A . Depression, somatization and the “new cross-cultural psychiatry” . Soc Sci Med 1977 ; 11 : 3 – 10 . Google Scholar CrossRef Search ADS PubMed 23 Kleinman A . Rethinking Psychiatry: From Cultural Category to Personal Experience . New York : Free Press , 1988 . 24 Lin KM , Cheung F . Mental health issues for Asian Americans . Psychiatr Serv 1999 ; 50 : 774 – 80 . Google Scholar CrossRef Search ADS PubMed 25 U.S. Department of Health and Human Services . Mental health: culture, race, and ethnicity a supplement to mental health: a report of the surgeon general . Rockville, MD , 2001 . 26 Gureje O , Simon GE , Ustun TB , Goldberg DP . Somatization in cross-cultural perspective: a World Health Organization study in primary care . Am J Psychiatry 1997 ; 154 : 989 – 95 . Google Scholar CrossRef Search ADS PubMed 27 Weisz JR , Weiss B , Suwanlert S , Chaiyasit W . Syndromal structure of psychopathology in children of Thailand and the United States . J Consult Clin Psychol 2003 ; 71 : 375 – 85 . Google Scholar CrossRef Search ADS PubMed 28 Canino G , Alegría M . Psychiatric diagnosis – is it universal or relative to culture? . J Child Psychol Psychiatry 2008 ; 49 : 237 – 50 . Google Scholar CrossRef Search ADS PubMed 29 Stickley A , Koyanagi A , Koposov R , et al. Loneliness and health risk behaviours among Russian and U.S. adolescents: a cross-sectional study . BMC Public Health 2014 ; 14 : 366 . Google Scholar CrossRef Search ADS PubMed 30 Weissberg RP , Voyce CK , Kasprow , et al. The Social and Health Assessment . Chicago, IL : Authors , 1991 . 31 Schwab-Stone M , Ayers TS , Kasprow W , et al. No safe haven: a study of violence exposure in an urban community . J Am Acad Child Adolesc Psychiatry 1995 ; 34 : 1343 – 52 . Google Scholar CrossRef Search ADS PubMed 32 Taylor DC , Szatmari P , Boyle MH , et al. Somatization and the vocabulary of everyday bodily experiences and concerns: a community study of adolescents . J Am Acad Child Adol Psychiatry 1996 ; 35 : 491 – 9 . Google Scholar CrossRef Search ADS 33 Birmaher B , Khetarpal S , Brent D , et al. The screen for child anxiety related emotional disorders (SCARED): scale construction and psychometric characteristics . J Am Acad Child Adolesc Psychiatry 1997 ; 36 : 545 – 53 . Google Scholar CrossRef Search ADS PubMed 34 March JS , Parker JD , Sullivan K , et al. The multidimensional anxiety scale for children (MASC): factor structure, reliability, and validity . J Am Acad Child Adolesc Psychiatry 1997 ; 36 : 554 – 65 . Google Scholar CrossRef Search ADS PubMed 35 Reynolds CR , Richmond BO . What I think and feel: a revised measure of children’s manifest anxiety . J Abnorm Child Psychol 1978 ; 6 : 271 – 80 . Google Scholar CrossRef Search ADS PubMed 36 Radloff LS . The CES-D scale: a self-report depression scale for research in the general population . Appl Psychol Meas 1977 ; 1 : 385 – 401 . Google Scholar CrossRef Search ADS 37 Roberts RE , Lewinsohn PM , Seeley JR . Screening for adolescent depression: a comparison of depression scales . J Am Acad Child Adolesc Psychiatry 1991 ; 30 : 58 – 66 . Google Scholar CrossRef Search ADS PubMed 38 Carpenter JS , Andrykowski MA , Wilson J , et al. Psychometrics for two short forms of the Center for Epidemiologic Studies-Depression Scale . Issues Ment Health Nurs 1998 ; 19 : 481 – 94 . Google Scholar CrossRef Search ADS PubMed 39 Henningsen P , Zimmermann T , Sattel H . Medically unexplained physical symptoms, anxiety, and depression: a meta-analytic review . Psychosom Med 2003 ; 65 : 528 – 33 . Google Scholar CrossRef Search ADS PubMed 40 Husain K , Browne T , Chalder T . A review of psychological models and interventions for medically unexplained somatic symptoms in children . Child Adolesc Ment Health 2007 ; 12 : 2 – 7 . Google Scholar CrossRef Search ADS 41 Goodman R , Slobodskaya H , Knyazev G . Russian child mental health - a cross-sectional study of prevalence and risk factors . Eur Child Adolesc Psychiatry 2005 ; 14 : 28 – 33 . Google Scholar CrossRef Search ADS PubMed 42 Perquin CW , Hazebroek-Kampschreur AM , Hunfeld JM , et al. Pain in children and adolescents: a common experience . Pain 2000 ; 87 : 51 – 8 . Google Scholar CrossRef Search ADS PubMed 43 Poikolainen K , Aalto-Setälä T , Marttunen M , et al. Predictors of somatic symptoms: a five year follow up of adolescents . Arch Dis Child 2000 ; 83 : 388 – 92 . Google Scholar CrossRef Search ADS PubMed © The Author(s) 2018. Published by Oxford University Press on behalf of the European Public Health Association. All rights reserved. This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/about_us/legal/notices) http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png The European Journal of Public Health Oxford University Press

Somatic symptoms and internalizing problems in urban youth: a cross-cultural comparison of Czech and Russian adolescents

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Oxford University Press
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© The Author(s) 2018. Published by Oxford University Press on behalf of the European Public Health Association. All rights reserved.
ISSN
1101-1262
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1464-360X
D.O.I.
10.1093/eurpub/cky001
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Abstract

Abstract Background Although the association between somatic complaints and internalizing problems (anxiety, somatic anxiety and depression) is well established, it remains unclear whether the pattern of this relationship differs by gender and in different cultures. The aim of this study was to examine cross-cultural and gender-specific differences in the association between somatic complaints and internalizing problems in youth from the Czech Republic and Russia. Methods The Social and Health Assessment, a self-report survey, was completed by representative community samples of adolescents, age 12–17 years, from the Czech Republic (N = 4770) and Russia (N = 2728). Results A strong association was observed between somatic complaints and internalizing psychopathology. Although the levels of internalizing problems differed by country and gender, they increased together with and largely in a similar way to somatic complaints for boys and girls in both countries. Conclusion The association between somatic symptoms and internalizing problems seems to be similar for boys and girls across cultures. Introduction Population-based studies suggest that somatic complaints are common among youth with nearly one-half of all children and adolescents reporting at least one symptom during the last 2 weeks.1,2 Types of somatic complaint vary with age,3 initially being monosymptomatic, they appear to become polysymptomatic over time.4 Somatic complaints often lack a medical explanation but indicate a higher risk of problems in several areas. They are also associated with an overuse of the health care system1,3 and increase the risk of unnecessary medical examinations and treatments.5 In general, somatic complaints have a negative impact on the quality of life, not only for the children themselves but also for their families,6 and may precede the development of somatic symptom disorders in adulthood.4 Somatic complaints are also associated with poor academic performance7 and school absence, which can lead to greater social isolation.8 There is also a strong association between somatic complaints and psychiatric problems, especially anxiety and depression.3,8 In depressed adolescents multiple somatic symptoms reflect a higher severity of depression9 and even in adolescents without a previous history of depression, somatic symptoms predict depression.10 Some studies have suggested that the association between somatic complaints and anxiety is stronger than the association between somatic complaints and depression,11 while others have indicated that the frequency of somatic complaints increases with the severity of depression, regardless of anxiety levels12 or that the association of somatic complaints with anxiety and depression may be of equal strength.13 In addition, the somatic component of anxiety (i.e. bodily symptoms of increased physiological arousal, such as an increase in heart rate and muscle tension)14 may have an independent role in the development of somatic complaints, even after controlling for internalizing problems.15 Girls typically report more somatic symptoms than boys.3,16 This gender difference seems to increase in puberty with adolescent girls reporting somatic symptoms at an increasing rate, while reporting levels in boys fall.17 It has been suggested that somatic symptoms in girls have a stronger association with anxiety and depression, while among boys they are more likely to be associated with disruptive behaviour.18 Some studies have suggested that the higher prevalence of anxiety and depression among females can fully account for gender differences in the reporting of somatic complaints,19 while others have shown that although gender differences decrease when adjusting for internalizing symptoms, they remain significant.20 There is some evidence that socio-cultural factors can influence the prevalence and nature of symptoms exhibited in somatization disorders.21 Some authors suggest that symptoms can be selectively expressed in ways accepted in a given culture22,23 and that the presentation of symptoms can depend on cultural attitudes that further determine how an illness is perceived and identified. For example, an earlier study showed that Asian patients were more likely to report somatic rather than emotional symptoms, although they did acknowledge having emotional symptoms when questioned further.24 Furthermore, explanatory models vary across cultures, with symptoms being attributed to medical illness, family, work, environmental stress or culture-specific phenomena.25 At the same time, a large cross-cultural study of somatization conducted by the World Health Organization (WHO)26 has indicated that the types of somatic complaint are fairly uniform throughout the world and are highly co-morbid with anxiety, depression and other psychiatric problems, and that there is an association between somatization disorder and significant functional impairment.26 Another study focusing on adolescents demonstrated that although many kinds of psychopathology were cross-culturally different, the level of somatic complaints was quite similar.27 Some studies have even suggested that the patterns of comorbidity, impairment, risk-factors and treatment seeking are cross-culturally similar, even though they may vary in magnitude or intensity.28 Although the association between somatic complaints, anxiety and depression is established, further research is needed to determine whether internalizing problems influence somatic complaints in different cultures in a similar fashion. This study aimed to investigate cross-cultural similarities (here represented by Russia and the Czech Republic) in the relation between somatic complaints and internalizing problems. The study hypothesized that an increased severity of somatic complaints relates to increasing levels of internalizing problems in both cultures in a similar way. We further hypothesized that these relationships are likely to be gender-specific, with higher levels of internalizing problems in relation to somatic complaints among girls. Methods Participants Data in this study come from the Social and Health Assessment (SAHA) conducted in the Czech Republic and Russia. The primary aim of this study was to determine the factors associated with adolescent health and well-being. The study sites were the following: Russia [the city of Arkhangelsk (population 356 000)] and the Czech Republic [the capital Prague (population 1.2 million) and all 12 regional capitals (population 50 000–400 000)]. The survey methodology has been previously described elsewhere.29 In brief, in Arkhangelsk and the Czech study locations, data were collected from representative samples of students aged 12–17 and 12–18, respectively. Only general public schools were included in the study (i.e. schools with special education programmes were excluded). Permission to conduct the study in selected schools was obtained from the respective city administrations. With regard to the Russian sample, ∼30 000 youth are in the 12- to 17-year-old age range in the city of Arkhangelsk. To obtain a representative sample, 14 schools were randomly selected from 71 eligible schools, yielding 210 classes in grades 6–11. For the Czech sample, stratified probability sampling of schools, according to location and school type, was conducted to identify a national probability sample of youth aged 12–18 years. The students that participated belonged to classes that had been randomly selected within randomly selected schools (N = 150 schools). For comparability, this study was limited to those adolescents who were aged 12–17 years old [M (SD) = 14.76 (1.55)] with the analytical sample thus comprising 2728 adolescents (1121 boys) from Russia and 4770 adolescents (2080 boys) from the Czech Republic. Response rates for these surveys were high, with only 3.6% of children refusing to participate in Russia and 1.4% in the Czech Republic (N = 98 and 67, respectively). Procedure In both countries, students completed the survey in their classrooms during a normal school day. Written informed consent was obtained from all participants prior to the survey administration, and both parents (for their children) and children had the right to refuse to participate. Ethical approval for the study was obtained from the Northern State Medical University in Arkhangelsk, Russia and the Institute of Psychology, Academy of Sciences of the Czech Republic, v.v.i. Measures The SAHA, a self-report questionnaire developed by Weissberg et al.30 and adapted by Schwab-Stone et al.31 served as the basis for this study. The instrument was originally developed in the USA in collaboration with the school system, to monitor the emotional and behavioural well-being of middle and high school students and to develop curricula to more adequately meet the needs of the students. All the measures, described below, were used in the SAHA survey and included both new scales that were specifically developed for the survey and pre-exisiting scales that had been used previously with similar populations. Somatic complaints were measured with a scale that consisted of nine items representing somatic symptoms commonly reported by children and adolescents. Only symptoms that had a prevalence rate above 5% (as suggested by Taylor et al.32 were used in this study). The scale items included felt my health should be better, had headaches, worried a lot about health, had stomach aches, had aches or pains, had nausea, had rashes or other skin problems, didn’t feel well and vomited. The ‘function loss’ symptoms were not included, as they tend to be uncommon (6–20 times less frequent than other somatic complaints29 and usually represent either a true loss of function or dissociative symptomatology). Students reported on somatic symptoms during the past month on a three-point scale [Not True (0), Somewhat True (1) and Certainly True (2)]. Cronbach’s α for this scale was 0.83. Three groups were formed according to the reported level of somatic complaints, namely those that reported relatively low levels of somatic complaints (the lower 75% of participants), those that reported a prevalence that fell between the 75th and 95th percentile, and finally those that reported the highest levels of somatic complaints, constituting the top 5%. These groups were subsequently categorized as ‘low’, ‘middle’ and ‘high’, respectively, in terms of the level of their somatic complaints. Somatic anxiety was assessed by a scale that consisted of seven items describing somatic experiences (bodily or physiological processes or sensations) frequently associated with anxiety in children and adolescents and commonly used in anxiety scales.33–35 Items in the present scale were compiled by the authors from existing scales and further modified and expanded after a series of discussions with a group of paediatricians, child psychiatrists and psychologists about the typical somatic symptoms experienced by children in relation to anxiety. Symptoms were listed after an introductory phrase (‘Often when I worry…’) with response options of ‘Not True (0), Somewhat True (1) or Certainly True (2) for you’. The scale items included I have trouble catching my breath; my heart beats fast; my hands feel sweaty; I feel shaky; I feel tense or uptight; my hands feel cold and I feel butterflies in my stomach. The scale does not overlap with the somatic complaints scale, as demonstrated previously by a joint factor analysis of the somatic anxiety and somatic complaints scales.15 The Cronbach α for the somatic anxiety scale was 0.78. Depressive symptoms were assessed using an adaptation of the Centre for Epidemiologic Studies-Depression Scale (CES-D).36 Both the CES-D37 and its modified/shortened versions38 have demonstrated excellent psychometric properties with adolescents. In this study, the questionnaire consisted of 10 items (i.e. I did not feel like eating, my appetite was poor; I felt that I could not shake off my sad feelings even with help from my family or friends; I felt lonely; I felt like crying; I felt really down; I felt that many bad things were my fault; I was tired; I have lost my interest in other people or things; I didn’t like myself and I felt bothered by people and things). Students reported on the presence of symptoms in the past month using a three-point scale [Not True (0), Somewhat True (1) and Certainly True (2)]. Scores were summed to create a total score that ranged from 0 to 20 with higher scores indicating increased depressive symptoms. The scale had good internal consistency (α 0.80). Anxiety was assessed by a 12-item scale,15 reflecting on cognitive–affective and behavioural modes of anxiety, including worrisome, preoccupying thoughts or unpleasant feelings about oneself or external stimuli (e.g. worrying about being liked; feeling nervous when called on in class and worrying about the future). Students reported on the presence of anxiety symptoms on a three-point scale [Not True (0), Somewhat True (1) and Certainly True (2)]. The scale had good internal consistency (α 0.86). Statistical analyses Data were analyzed using the Statistical Package for the Social Sciences (SPSS-22.0). Univariate analyses of covariance (Uni-ANCOVA) were conducted to assess differences in the levels of somatic symptoms between girls and boys in the two countries (with age used as a covariate). Multivariate analyses of covariance (MANCOVA) were performed to assess differences in the levels of internalizing problems (as assessed by depressive, anxiety and somatic anxiety symptoms) in boys and girls, who were divided into three groups in relation to the reported levels of somatic complaints (‘low’, ‘middle’ and ‘high’). Hence, we used a 3 (level of somatic complaints) × 2 (country) × 2 (gender) design for the internalizing problems, while controlling for age as a covariate. Results Table 1 presents the descriptive statistics [M (SD)] for the MANCOVA regarding differences in internalizing problems according to the level of somatic complaints for boys and girls in both countries. The Univariate Analysis of Variance revealed significantly higher levels of somatic complaints in girls in both countries: [M (SD) = 4.99(3.67) in girls vs. 3.61(3.06) in boys in the Czech Republic and M (SD) = 5.53(3.64) in girls vs. 4.59(3.64) in boys in Russia]. The between-subject effects (with age used as a covariate) were significant for country F(1, 7607) = 930.04, η2 = 0.011, P < 0.001; for gender F(1, 7607) = 2271.90, η2 = 0.025, P < 0.001 and for the interaction effect of country by gender F(1, 7607) = 87.59, η2 = 0.001, P < 0.01. The effect of age was also significant [F(1, 7607) = 201.02, η2 = 0.002, P < 0.001], suggesting higher levels of somatic complaints in older youth. Table 1 Internalizing scores [M (SD)] in the Czech Republic and Russia by the level of somatic complaints in boys (B) and girls (G) Level of somatic complaints Low Middle High Depressive symptoms Czech B 2.71 (2.70) 5.59 (3.78) 8.29 (4.70) G 3.81 (3.39) 6.82 (4.13) 10.22 (4.63) Russia B 3.94 (3.42) 6.71 (4.13) 8.72 (4.44) G 5.19 (3.82) 7.79 (3.85) 10.12 (4.13) Anxiety Czech B 8.06 (4.50) 10.90 (4.59) 11.37 (5.83) G 9.67 (4.41) 12.01 (4.51) 14.17 (4.77) Russia B 11.52 (5.80) 13.27 (5.52) 14.75 (5.17) G 12.75 (5.46) 15.21 (5.17) 16.64 (4.92) Somatic anxiety Czech B 2.70 (2.30) 4.25 (2.80) 5.74 (3.61) G 4.10 (2.59) 5.87 (2.75) 7.31 (3.10) Russia B 2.94 (2.55) 4.33 (2.93) 6.06 (4.00) G 4.22 (2.69) 5.45 (2.92) 6.94 (3.14) Level of somatic complaints Low Middle High Depressive symptoms Czech B 2.71 (2.70) 5.59 (3.78) 8.29 (4.70) G 3.81 (3.39) 6.82 (4.13) 10.22 (4.63) Russia B 3.94 (3.42) 6.71 (4.13) 8.72 (4.44) G 5.19 (3.82) 7.79 (3.85) 10.12 (4.13) Anxiety Czech B 8.06 (4.50) 10.90 (4.59) 11.37 (5.83) G 9.67 (4.41) 12.01 (4.51) 14.17 (4.77) Russia B 11.52 (5.80) 13.27 (5.52) 14.75 (5.17) G 12.75 (5.46) 15.21 (5.17) 16.64 (4.92) Somatic anxiety Czech B 2.70 (2.30) 4.25 (2.80) 5.74 (3.61) G 4.10 (2.59) 5.87 (2.75) 7.31 (3.10) Russia B 2.94 (2.55) 4.33 (2.93) 6.06 (4.00) G 4.22 (2.69) 5.45 (2.92) 6.94 (3.14) Table 1 Internalizing scores [M (SD)] in the Czech Republic and Russia by the level of somatic complaints in boys (B) and girls (G) Level of somatic complaints Low Middle High Depressive symptoms Czech B 2.71 (2.70) 5.59 (3.78) 8.29 (4.70) G 3.81 (3.39) 6.82 (4.13) 10.22 (4.63) Russia B 3.94 (3.42) 6.71 (4.13) 8.72 (4.44) G 5.19 (3.82) 7.79 (3.85) 10.12 (4.13) Anxiety Czech B 8.06 (4.50) 10.90 (4.59) 11.37 (5.83) G 9.67 (4.41) 12.01 (4.51) 14.17 (4.77) Russia B 11.52 (5.80) 13.27 (5.52) 14.75 (5.17) G 12.75 (5.46) 15.21 (5.17) 16.64 (4.92) Somatic anxiety Czech B 2.70 (2.30) 4.25 (2.80) 5.74 (3.61) G 4.10 (2.59) 5.87 (2.75) 7.31 (3.10) Russia B 2.94 (2.55) 4.33 (2.93) 6.06 (4.00) G 4.22 (2.69) 5.45 (2.92) 6.94 (3.14) Level of somatic complaints Low Middle High Depressive symptoms Czech B 2.71 (2.70) 5.59 (3.78) 8.29 (4.70) G 3.81 (3.39) 6.82 (4.13) 10.22 (4.63) Russia B 3.94 (3.42) 6.71 (4.13) 8.72 (4.44) G 5.19 (3.82) 7.79 (3.85) 10.12 (4.13) Anxiety Czech B 8.06 (4.50) 10.90 (4.59) 11.37 (5.83) G 9.67 (4.41) 12.01 (4.51) 14.17 (4.77) Russia B 11.52 (5.80) 13.27 (5.52) 14.75 (5.17) G 12.75 (5.46) 15.21 (5.17) 16.64 (4.92) Somatic anxiety Czech B 2.70 (2.30) 4.25 (2.80) 5.74 (3.61) G 4.10 (2.59) 5.87 (2.75) 7.31 (3.10) Russia B 2.94 (2.55) 4.33 (2.93) 6.06 (4.00) G 4.22 (2.69) 5.45 (2.92) 6.94 (3.14) The main effect for the level of somatic complaints for the total group was significant [Wilks’ lambda = 0.810; F(6, 14 966) = 276.53, P < 0.000, η2 = 0.010], with increasing internalizing problems associated with an increasing level of somatic complaints. The main effect for gender was significant [Wilks’ lambda = 0.972; F(3, 7483) = 72.73, P < 0.000, η2 = 0.028], demonstrating a difference between the variables of interest for boys and girls. The main effect for country was significant [Wilks’ lambda = 0.958; F(3, 7483) = 108.73, P < 0.000, η2 = 0.042], suggesting differences in the baseline levels of internalizing problems between youth in the Czech Republic and in Russia (higher in Russia). The main effect for age was also significant [Wilks’ lambda = 0.984; F(3, 7483) = 39.93, P < 0.000, η2 = 0.016], demonstrating a difference between the variables of interest by age. Pearson’s correlational analyses showed a clear increase in symptoms with increasing age (data not shown). In regard to the interaction effects, the interaction effect for somatic complaints × country was weakly significant [Wilks’ lambda = 0.998; F(6, 14 966) = 2.71, P < 0.05, η2 = 0.001], suggesting that the increase in internalizing problems that occurs along with an increase in somatic complaints follows a slightly different pattern in these two cultures. However, the interaction effect for somatic complaints × gender was not significant [Wilks’ lambda = 0.999; F(6, 14 966) = 1.06, n.s., η2 = 0.000], which indicates that patterns of internalizing problems in relation to somatic complaints were not gender-specific. The interaction effect for country × gender was not significant [Wilks’ lambda = 0.999; F(3, 7483) = 1.73, n.s., η2 = 0.001], suggesting that the relation between internalizing problems and somatic complaints in boys and girls was similar in both countries. Finally, the interaction effect for somatic complaints × country × gender was also not significant [Wilks’ lambda = 0.998; F(6, 14 966) = 2.15, n.s., η2 = 0.001]. This suggests that despite substantial differences in the levels of internalizing problems by country, by gender and by the different levels of somatic complaints, that internalizing problems and somatic complaints increase together in a similar way among boys and girls in both countries. Table 2 presents effect sizes for each dependent variable (depressive, anxiety and somatic anxiety symptoms), as well as the summary statistics. In both samples, all three types of internalizing problem increased along with the level of somatic complaints and the age of the participants. The results suggest that the interaction effect of somatic complaints × country on internalizing problems was predominantly related to differences in co-morbid depressive symptoms. Table 2 Effect sizes for each dependent variable and summary statistics (η2, P) Depressive symptoms Anxiety symptoms Somatic anxiety Age 0.009, <0.001 0.001, <0.05 0.005, <0.001 Somatic complaints 0.161, <0.001 0.057, <0.001 0.092, <0.001 Country 0.004, <0.001 0.035, <0.001 0.000, ns Gender 0.012, <0.001 0.012, <0.001 0.022, <0.001 Somatic complaints by country 0.001, <0.05 0.000, ns 0.001, ns Country by gender 0.000, ns 0.000, ns 0.001, <0.05 Somatic complaints by gender 0.000, ns 0.000, ns 0.000, ns Somatic complaints by country by gender 0.000, ns 0.001, ns 0.000, ns Depressive symptoms Anxiety symptoms Somatic anxiety Age 0.009, <0.001 0.001, <0.05 0.005, <0.001 Somatic complaints 0.161, <0.001 0.057, <0.001 0.092, <0.001 Country 0.004, <0.001 0.035, <0.001 0.000, ns Gender 0.012, <0.001 0.012, <0.001 0.022, <0.001 Somatic complaints by country 0.001, <0.05 0.000, ns 0.001, ns Country by gender 0.000, ns 0.000, ns 0.001, <0.05 Somatic complaints by gender 0.000, ns 0.000, ns 0.000, ns Somatic complaints by country by gender 0.000, ns 0.001, ns 0.000, ns Table 2 Effect sizes for each dependent variable and summary statistics (η2, P) Depressive symptoms Anxiety symptoms Somatic anxiety Age 0.009, <0.001 0.001, <0.05 0.005, <0.001 Somatic complaints 0.161, <0.001 0.057, <0.001 0.092, <0.001 Country 0.004, <0.001 0.035, <0.001 0.000, ns Gender 0.012, <0.001 0.012, <0.001 0.022, <0.001 Somatic complaints by country 0.001, <0.05 0.000, ns 0.001, ns Country by gender 0.000, ns 0.000, ns 0.001, <0.05 Somatic complaints by gender 0.000, ns 0.000, ns 0.000, ns Somatic complaints by country by gender 0.000, ns 0.001, ns 0.000, ns Depressive symptoms Anxiety symptoms Somatic anxiety Age 0.009, <0.001 0.001, <0.05 0.005, <0.001 Somatic complaints 0.161, <0.001 0.057, <0.001 0.092, <0.001 Country 0.004, <0.001 0.035, <0.001 0.000, ns Gender 0.012, <0.001 0.012, <0.001 0.022, <0.001 Somatic complaints by country 0.001, <0.05 0.000, ns 0.001, ns Country by gender 0.000, ns 0.000, ns 0.001, <0.05 Somatic complaints by gender 0.000, ns 0.000, ns 0.000, ns Somatic complaints by country by gender 0.000, ns 0.001, ns 0.000, ns As the differences by outcome, country and gender might have been masked by use of the MANCOVA analysis (i.e. by simultaneously assessing all three outcomes in one model), we also attempted to examine each outcome separately to determine whether the patterns that are reported from the MANCOVA were the same for each outcome individually. This produced very similar results. Discussion In this study, we sought to investigate the relationship between somatic complaints and internalizing problems in a cross-cultural context, and to examine whether the association is country and gender specific. The hypothesis that the relation between somatic complaints and internalizing problems is the same across cultures was not confirmed, with the relation between depressive symptoms and somatic complaints seeming to underlie the slightly different patterns observed in the two countries. We further hypothesized that the relationship between somatic complaints and internalizing problems is different among boys and girls but this hypothesis was refuted, as the results suggest that internalizing problems and somatic complaints increase in a similar, non–gender-specific way in both countries. In general, our results provide strong support for the earlier established association between somatic symptoms, on the one hand, and anxiety and depression, on the other hand, where an increase in the number of somatic complaints was accompanied by an increase in the level of internalizing problems. Effect sizes for the association were moderate, which is in line with the results from some previous studies39 and points to the fact that somatic symptoms may occur without concurrent anxiety or depression and hence, are not solely bodily expressions of internalizing problems. In addition, our study confirmed the previously suggested association between somatic anxiety and somatic complaints,15 further supporting the finding that somatic anxiety is associated with somatic complaints independently of anxiety and depression. This finding may have implications for clinical practice especially when selecting an intervention as it suggests that somatic anxiety may be one reason for children to have a focus on their bodily feelings that further leads to somatization. Cognitive–behavioural interventions commonly have a primary focus on treating either physical symptoms (e.g. pain) or anxiety, although they do demonstrate some efficacy for reducing somatic symptoms.40 However, using such cognitive–behavioural interventions may be more beneficial if they also consider the interaction of physical complaints and anxiety. As to our first hypothesis, Russian youths generally reported higher levels of internalizing problems than those in the Czech Republic, although it is uncertain whether the results from this representative sample from the north of Russia can be generalized to the general adolescent population in the whole of Russia. Interestingly, the relation between internalizing and somatic symptoms was slightly different in the Czech Republic and Russia, which was related to the differential influence of depressive symptoms. The question about the specific nature of such cultural influences needs to be approached with other research designs. So far, there have been surprisingly few studies on mental health problems in adolescents from Eastern Europe in general, or in Russian or Czech youth, in particular. A study comparing Russian and British children found that the patterns of internalizing and externalizing problems were similar between the two groups, even though Russian children had a somewhat higher level of symptoms.41 Somatization has previously been thought to be particularly common in non-Western cultures but conclusions are complicated by the lack of comparable standardized methodologies, as diagnostic criteria derived from one culture may not necessarily be applicable to another. A large cross-cultural study of somatization conducted by the WHO found that although the rates of somatization varied markedly across cultures, no clear cultural, economic or geographic factors could be identified to account for the variation.26 Another study demonstrated that although many kinds of psychopathology in adolescents were cross-culturally different, the levels of somatic complaints were quite similar.27 Contrary to our second hypothesis, the patterns of increase in internalizing problems in relation to the increase in somatic complaints were not gender-specific. This suggests that gender-specific differences in the prevalence of anxiety and depression may not fully account for differences in somatic symptoms. Similar findings have been reported by Haug et al.13 who also found that the association between somatic complaints and internalizing problems was equally strong in men and women13 but differ from those by Beck8 and Perquin et al.42 who reported gender-specific patterns in the association, with girls tending to report not only more anxiety and depression but also more somatic symptoms than do boys. This study has a number of limitations. First, as this study used adolescent self-reports, the possibility of recall bias and false reporting cannot be excluded.43 Second, we also lacked any relevant medical information (doctor’s reports etc.,) which means that we cannot rule out the possibility that the reported symptoms might have been explained by a medical condition. Third, the somatic complaints scale that was used in this study was limited to nine items and did not take into consideration the potential presence of culture-specific symptoms. Fourth, selection bias can often be an issue in population-based studies, although we would argue that it was unlikely to have been a problem in this study considering the thorough randomization procedure and low refusal rate. Finally, the cross-sectional nature of the study does not allow conclusions to be drawn about causality or the direction of the relationship between somatic complaints and internalizing problems. The study’s strengths are a large sample size, high response rates and a focus on less common study groups: geographically representative samples from the Czech Republic and Russia. The scales we used allowed us to control for the possible overlap between depression, anxiety, somatic anxiety and somatic symptoms, thus making it possible to assess the contribution of these conditions separately. Future research should consider validating somatic symptoms by medical examination, complementing self-reports by obtaining additional information from sources like parents or medical records, as well as include more items on somatic symptoms and their consequences. Even if somatic symptoms are influenced by culture in their presentation, the presence of an association with psychopathology seems to be independent of culture in boys and girls, supporting the notion that similar treatment methods may be used in different countries.28 Studying the association between somatic and psychological symptoms may be a promising method to discover cultural differences concerning symptom development that can be used as a complement to only comparing symptom frequencies per se. Future research should address how such differences could be interpreted, as well as assess the extent to which somatic complaints impact on the daily life of youths, lead to functional impairment and/or health care seeking behaviour from a cross-cultural perspective. Funding This work was supported by Czech Republic for long-term strategic development of research organization (grant number RVO: 68081740). Conflicts of interest: None declared. Key points Results strongly support the earlier established association between somatic symptoms and anxiety and depression. Evidence indicates that the level of internalizing problems increases along with the level of somatic complaints. The patterns of association between somatic complaints and internalizing problems are similar for boys and girls in different cultures. 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The European Journal of Public HealthOxford University Press

Published: Jan 24, 2018

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